DE3241022A1 - CAR TELEPHONE - Google Patents

Description

October 5, 1982 Fd / Le,

ROBERT BOSCH GMBH, 7000 STUTTGART 1

Car phone
State of the art

The invention is based on a route guidance system for vehicles according to the preamble of the main claim. From DE-OS 25 15 66O a traffic route guidance system is already known that works with built-in road loops. If a vehicle drives over such road loops, messages are transmitted between the vehicle and an exchange, which automatically transmit important information such as directions, road conditions, favorable speed, etc. to the vehicle driver on a display panel after the destination has been named. Such traffic route guidance systems are furthermore in the European patent application 79 100 732.1, in Radio Mentor Electronics, volume hk, issue 3, 1978, Berlin, page 103 to page 108 "ALI system for route guidance and traffic data acquisition" and in the NTZ, volume 28 issue 8, 1975, pages 306 to 308 "Electronic guide for motorists" has been described. The known arrangements have the disadvantage that a return

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notification of the vehicle driver to transfer information is not possible. Furthermore are computer controlled Telephone systems "known, for example under the name OFi) -D are manufactured by the Bosch company. These computer-controlled telephone systems have a transmitter and a receiver, the radio transmission to a relay station enables. The signals are usually transmitted in the VHF range. These well-known telephone arrangements However, they are very expensive and also unreliable, since on the one hand a high level of effort for the security of the Transmission must be given and, on the other hand, only a few frequency ranges are available, so that the telephone subscriber often does not find a free channel. Another disadvantage of the computer-controlled radio telephones it is to be seen that the security against eavesdropping is not given.

Advantages of the invention

The route guidance system according to the invention with the characteristic Features of the main claim has the advantage that on the one hand already existing facilities of the route guidance system and, on the other hand, the number of channels for conversation Can be adapted to requirements at any time. Another advantage is that such car telephones are inexpensive can be produced so that, in conjunction with the large number of channels, a wide distribution of the telephone system is possible is. The system also has the advantage that unauthorized eavesdropping on conversations is hardly possible.

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The measures listed in the subclaims enable advantageous developments and improvements of the route guidance system specified in the main claim. It is advantageous not only to limit the transmission of analog and digital voice signals in both directions to the route guidance system, for example to the road maintenance depot, but to provide a connection to the public telephone network. This makes it possible to make telephone calls in the public telephone network in the area of road loops. In order to achieve the simplest possible configuration of the telephone, ^{it is} advantageous to modulate the channels provided for the exchange of route guidance data with the voice frequencies. Major modifications and expansions of the already known route guidance system are not necessary. It is expedient to use known types of modulation, with amplitude or frequency modulation being particularly advantageous. If pulse code modulation is used, it is still possible to use the channels provided for the route guidance data unchanged, since in this case the voice transmission is also digital. In order to enable two-way communication, it is advantageous for the transmission between the vehicle device and the road device to take place word for word alternately in both directions. Since the transmission is digital, it is particularly advantageous that the data transmission modules provided for the route guidance system are used for this purpose. The auxiliary frequencies for the transmitter and the receiver are expediently derived from the timing of the route guidance system. The telephone transmission can then be designed particularly easily if one channel is used for talking back and forth.

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is used. The signals for the back and forth talk are split up by means of hybrid circuits in the loop device. The dialing and auxiliary pulses, for example the charge pulses , are expediently transmitted as a digital signal via the channels of the route guidance system. This means that the existing facilities can continue to be used in full and without changes. One Another possibility is to use the dialing and auxiliary impulses to be transmitted via audio frequencies in the voice channel. This type of transmission is required when processing the pulses a little effort. To monitor charges and to prevent misuse, it is advantageous to if a code is requested from the on-board unit before the telephone connection is established. A simple one Charge monitoring is possible if the charges are temporarily stored in the loop device with a key or code number and can be called up there by the exchange or if modules are in the on-board unit are available for which the charges can be debited due to charge impulses.

To the on-board unit, which is designed for traffic route guidance is also to be used for telephone traffic, it is only necessary to add another transmitter and one to provide additional receivers to which the voice transmission is switched. This sender and receiver are controlled by auxiliary frequencies that are out of sync of the information system are obtained. The other transmitter and receivers operate advantageously with amplitudes or Frequency modulation. This allows the device to be expanded most inexpensively.

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Another advantageous option for expansion of the vehicle device for traffic guidance is given by the fact that analog-digital converter and digital-analog converter are provided for converting the speech signals and the digital signals obtained in this way instead of the route guidance information are transmitted on the corresponding channels. As a result, there are only very minor ones Interventions in the route guidance system necessary. It is also beneficial to provide registers in which the converted signals can be stored. This enables two-way communication to be achieved in a simple manner, by alternately sending the stored signals and then receiving them. It is also advantageous to attach a moving element to the vehicle so that the telephone mode can only be switched over to when the motion sensor reports that the vehicle has come to a standstill. This ensures that during the Telephone connection, the vehicle cannot leave the area of a road loop. Furthermore, it is cheap the microcomputer as a telephone number memory and number repeater to use. It is also advantageous to use the route guidance system according to the invention with a euro signal receiver connect to. This has the advantage that the vehicle driver can always be reached via Euro signal and in the event of a signal by means of the telephone according to the invention, can call an agreed location.

drawing

Embodiments of the invention are shown in the drawing shown and explained in more detail in the following description. FIG. 1 shows a first exemplary embodiment

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a telephone according to the invention, FIG. 2 an embodiment of a control device located on the road that is suitable for telephone transmission, FIG. 3 shows a second embodiment of a vehicle telephone according to the invention and FIG. k shows another example of a control device located on the road that is suitable for telephone transmission.

Description of the exemplary embodiments

Traffic guidance systems for motorways and expressways have long been known. In a well-known traffic route guidance system, which was presented under the name ALI induction loops are embedded in the street. These induction loops are located directly on the street or in parking lots and motorway entrances. The induction loops are each connected to a process computer, which in turn via data lines with a central computing device communicates. This is a traffic flow optimization possible by influencing traffic using traffic data acquisition. The contact with the car driver takes place via a car device to which messages are transmitted via the induction loop will. The information is provided in two directions. The driver must have his destination in the form before starting Enter a decimal number in the on-board unit. When driving over an induction loop, the on-board unit will activated and these data transferred to the process computer. The computer then individually determines how the driver of the vehicle has his special target on the

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the shortest way in terms of time.

The principle of interactive transmission is based on that one provided with transmitter, receiver, destination input keyboard and optical display panel as well as a special antenna Vehicle reports presence and desired destination when entering the system area. The information will be recorded in an induction loop and initially on forwarded to a street device. The memory of the microcomputer in the road device is used for the special Direction recommendations given by the vehicle removed and transferred back to the vehicle via the same induction loop. The directions contain recommendations also speed recommendations as well as messages about the risk of traffic jams, fog and ice. details about the specific structure of the vehicle devices as well as the road loops and the computing devices in addition to the publications already mentioned, the BMFT report "Field testing of a route guidance and information system for motorists (ALI) ".

It is based on this by means of the transmitting and receiving unit in the motor vehicle and the associated antenna In principle, it is possible to receive and send data other than traffic-related data. This leads to the possibility the data transmission designed for traffic information and receiving unit%, also for the transmission of To use phone calls or other information.

While the traffic information communication takes place at certain locations during the journey and has to take place in part, it is possible to _Λ the wireless connection to the public telephone network ζ via loops /

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build that under marked parking lots, hard shoulder of the carriageway or under other public accessible terrain, so that telephone calls are possible from a stationary vehicle. The stationary telephone data station consists of one under the instead of a telephone booth Road surface laid loop and additional Devices for the transmission of the voice and the on-board unit from an additional device which the Enables voice transmission via the vehicle device. These Facilities translate the usual signals of speech transmission on both sides of the interface into a form secure transmission via the traffic information system guaranteed. In addition, it is possible to accommodate a Euro signal receiver in the vehicle, so that the driver can also be reached via Eurosignal while driving with the request to call a specific location. The driver heads for the next parking lot, which is known as the "telephone loop parking lot" is marked. Picking up the telephone receiver in the vehicle leads the in a known manner Search for a free channel in the loop device, determines the correct and safe signal transmission and gives the usual dial tone. Now the conventional one Dialing of the desired participant started, the conversation carried out in the usual way and completed. The number of charge units used is recorded either in the on-board device or in the loop device registered.

In addition to the telephone, the vehicle on-board equipment all equipment included in the stationary

Telecommunication operations have already been introduced (e.g. video text devices). The system has been expanded to include devices that are connected to the public telephone network are connectable. ·

FIG. 1 shows a device installed in the vehicle which, in addition to receiving and transmitting traffic information, is also suitable for transmitting telephone calls. The normal vehicle device contains a microprocessor 1 which is provided with memories for the program and for the data. This microprocessor 1 has access via a control bus 12 to a display and operating part 3, to a switchable transceiver k _t to input and output modules 2 ₅ 10 and as well as to a clock processing unit 9, a transmitter 7 and a receiver 8 The aforementioned assemblies are connected to the data bus 13 of the microcomputer via the input and output circuits 2, 10 and 11. The transmitters and receivers k , J and 8 are additionally connected to a ferrite antenna 5 which, for data transport, is connected to the loop of the Furthermore, a position transmitter 6 is provided which is connected to the input and output module 11. Apart from the modules 7, 8 and 9, the other groups are contained in every traffic information device and are described in detail in the cited publications.

To connect a telephone to a traffic information loop, the transmitter 8 and the receiver 7 are also required. They use the same ferrite antenna as the transceiver unit k of the traffic information device.

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FIG. 2 shows the loop device for connecting the car telephone to the public telephone. The microcomputer 20 of the loop device is connected to the input and output module 21, the transceiver 22, a transmitter 2k , a receiver 25j, a clock processor 31 and a dialing device 27 via a control bus 28. The data bus 29 is connected to the dialing device 27, the clock processor 31 and, via the input / output module 28, to the transceiver 22. Of the. Transceiver 22 corresponds to that of a normal traffic information loop device. The transceiver 22 is connected to the loop 23. As with the vehicle device, the transmitter 2k, the receiver 25 and the clock processor 31 are required for the telephone connection. The transmitter 2k and the receiver 25 are connected to a hybrid circuit 26. The hybrid circuit causes the "split" into the forward and backward channels required for intercom and is well known from telephone technology. Dialing device 27 is also required for connection to the telephone line. which is connected to the dialing device via the control bus 28 and the data bus 29.

A telephone connection now has the following sequence: If the driver intends to make a phone call, he drives to the next parking space, which has a corresponding telephone loop having. If the vehicle has come to a standstill, which is recognized by the encoder 6, the transmits Microcomputer 20 of the loop device via the transceiver 22 and the loop 23 call steps, like this is the case with the normal traffic information system. the

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However, the number of call steps can be greatly reduced compared to the traffic information system. Approximately one call step per second is sufficient. If the driver is in a marked loop position and his vehicle has come to a standstill, he picks up the telephone receiver 1 h of the vehicle device, which in turn is connected to the transmitter 8 and the receiver 7. The microcomputer 1 of the vehicle device now responds to the next call step of the loop device with a data telegram as it is known from traffic information transmission. Only the keyword, for example in byte 1 of the telegram, has been changed. In the normal traffic information mode, the vehicle number and the private telephone number of the car driver can now be transmitted to record charges. For additional security, it is possible, for example, to transmit a code word in the form of a multi-digit decimal number. The microprocessor 20 of the loop device now waits for _{the dial tone of the office via the dialing device 2T 9} which is connected to the public telephone network via line 30. The dial tone is now transmitted to the vehicle device via the data channel of the traffic information system.

The driver can now call the desired phone number Enter 3 using the keypad of the control unit. Subscriber numbers can also be used to increase convenience already be stored in a memory of the microprocessor 1 and accessed from there. the desired subscriber number is now on the Verkehrsinf ormationskänal to the microcomputer 20 of the loop device transfer. This is via the dialer

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27 trigger the normal dialing process. It is expedient if an automatic redial takes place, if there is an busy signal during or after the dialing process is reported back.

When the callsign is sent from the office, the microcomputer 20 of the loop device forwards this message to the vehicle device via a data channel of the traffic information system. Now the microcomputer 1 of the vehicle device and the microcomputer 20 of the loop device switch off the traffic information transmission receivers k and 22 and the transmitters 8 and 2k and the receivers 7 and 25 on. A direct connection to the telephone receiver is now established from the telephone line via the dialing device 27 * via the hybrid circuit 2β and via the transmitter and receiver. The rest of the process is the same as for a normal telephone call. The microcomputer of the vehicle device 1 and the loop device 20 now control via their receivers 7 and 25 ₅ whether the connection still exists. If the driver puts the handset on ₉ , the vehicle microcomputer 1 switches off the transmitter -S and the microcomputer 20 of the loop device recognizes the end of the telephone call from the missing reception signal and also switches to the data exchange of traffic information. At the same time he interrupts the connection to the telephone line by means of the dialing device 27.

When the telephone call is terminated by the remote subscriber, the microcomputer 20 of the loop device recognizes the termination of the telephone call via the dialing device 27. He switches off the transmitter 2k and the

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Transceiver assembly 22 a. Recognizes accordingly Now the microcomputer 1 of the on-board unit over the lack of the received signal the termination of the telephone connection. A visual and / or acoustic signaling prompts the driver to pick up the phone hang up.

Since the loop device after the telephone connection was interrupted going back to call step mode is the loop free for further telephone connections.

Instead of the analog transmission of the telephone conversation, a digital transmission of the telephone conversation is also possible. An exemplary embodiment for the vehicle device is shown in FIG. The vehicle device for telephone calls and for traffic information transmission again contains the microprocessor 1 + 0 required for normal traffic information transmission. The microprocessor 1 + 0 is connected to input and output circuits 1 + 1, 1 + 2 and 1 + 3 via a control bus 53. Furthermore, the control bus is led to an analog-to-digital converter 1 + 9 , a digital-to-analog converter 50, a register 51, a register 52 and to input and output circuits kh and 1 + 5. The data bus 5 ^ leads from the microprocessor 1 * 0 via the input and output module h 1 to a control unit 1 + 6 and to the input and output circuits 1 + 2, 1 + 3 »^ and 1 + 5. and output module 1 + 2, a transceiver 1 + 7 is controlled, the output of which is connected to a ferrite antenna 55. The encoder 6 is connected to the input and output module U3. A telephone receiver 1 + 8 is connected to the Α / Γ converter Ij.9 and the D / A converter 50.

Instead of the modules required for the analog connection The digital converter groups 1 + 9 and and the registers 51 and 52 now appear. The analog-to-digital converter 1 + 9

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has a microphone amplifier, a low-pass filter with a cut-off frequency of 3, ^ · kHz and a sample and hold circuit for kHz and processes an 8-bit signal in accordance with the CCITT recommendation. The digital values formed in accordance with the analog signal are transferred to register 51. In addition to a digital-to-analog converter according to the CCITT recommendation, the digital-to-analog converter 50 has a low-pass filter with the cut-off frequency of 3 kHz and an amplifier for driving the listener. The operation of this circuit arrangement will be explained in connection with the loop device, which is shown in figure h, closer.

The microprocessor 60 is connected with its control bus 61 and its data bus 62 with the other assemblies of the loop device. Registers 6f and 68 are controlled via input and output circuits 63, 6k and 65, which in turn are each equipped with an analog-to-digital converter 69 and a digital-to-analog converter.

70 are connected. To the digital-to-analog converter TO and to the analog-to-digital converter 69 is a hybrid circuit

71 connected, which in turn is connected to the dialing device 72. A telephone line 73 leads from the dialing device 72 to the exchange (not shown). Furthermore, a transceiver 66 is provided, to the output of which the loop 7 ^ · is connected.

A telephone connection is established with regard to the dialing process as described above. If, however, the call sign is recognized by the dialing device 72 via the telephone line, the microcomputer 60 of the loop device sends a special code word to the vehicle device via the traffic information data channel. The microcomputers kO and

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of the vehicle device and the loop device now see the transceiver groups hj and 72 to FFSK (fast frequency shift keying). An 8-bit word each from registers 51, 52 or 67, 68 is now alternately exchanged between the vehicle and the loop via the transmitter-receiver assemblies hj and 72. Since the data rate in FFSK mode can be up to 96 kBit per second, for example, and an 8-bit wide word is temporarily stored in the registers, the result is a quasi-continuous data transport in both directions of U8 kBit per second, which corresponds to the CCITT recommendations. The voice is transmitted via the data transmission channels that are otherwise used for the transmission of traffic information. Special devices that can be modulated in an analog manner are therefore not required.

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Claims (1)

October 5, 1982 Fd / Le ROBERT BOSCH GMBH, 7OOO STUTTGART 1 Expectations M λ route guidance system for vehicles with digital data exchange between vehicle devices and road devices, • whereby the vehicle devices and the road devices preferably have inductive transmitting and receiving devices, characterized in that at least some of the paths provided for data transmission are provided for the transmission of analog or digital voice signals. 2. Destination guidance system according to claim 1, characterized in that that the road device to transmit the analog or digital voice signals along with auxiliary signals to a preferably public telephone network is connectable. 3. Destination guidance system according to claim T or 2, characterized in that that the channels provided for the exchange of routing data are modulated by the speech frequencies are. k. Route guidance system according to Claim 3, characterized in that the modulation takes place as amplitude or frequency modulation. 5. Destination guidance system according to claim 3, characterized in that that the modulation takes place as a pulse code modulation. 6. Destination guidance system according to claim 5, characterized in that that the transmission between the on-board unit and the road unit alternates word for word in both Directions takes place. 7. route guidance system according to claim 5 or 6, characterized characterized in that the transmission for the route guidance system provided data transmission modules are used. 8. route guidance system according to one of claims 1 to 7, characterized in that the auxiliary sf req.uenzen for the transmitter (8, 2h) and receiver (U, 25) are derived from the clock of the route guidance system. 9. route guidance system according to one of claims 1 to 8, characterized in that one channel is used for speaking back and forth. 10. Destination guidance system according to one of claims 1 to 9, characterized in that hybrid circuits (96, 71) in the loop devices, the split into two-way and two-way speaking make. 11. Route guidance system according to one of claims 1 to 10, characterized in that the dialing and auxiliary pulses as a digital signal via the channels of the route guidance system are transferred. BATH ORIGINAL 12. Destination guidance system according to one of claims 1 to 10, characterized in that the dialing and auxiliary pulses are transmitted via audio frequencies in the voice channel. 13. Destination guidance system according to one of claims 1 to 12, characterized in that a code of the vehicle device is queried before a connection is established. 1U. Target guidance system according to claim 13, characterized in that that the code is formed from the vehicle number and a subscriber number. 15 route guidance system according to one of claims 1 to 1 k , characterized in that the switchover from route guidance to telephone operation takes place by means of a keyword. 16. Destination guidance system according to one of claims 13 to 15, characterized in that data on charges are temporarily stored in the loop device with the key or code number are. 17 · Destination guidance system according to claim 1 β, characterized in that that the charge data can be called up from an exchange. 18. Device arranged in a vehicle for route guidance for systems according to one of claims 1 to 17, with a microcomputer to control the functional processes and with a transmitting and receiving device for Exchange of data with a road device, characterized in that a further transmitter (8) and a further receiver (7) are provided, to which a switch is made during voice transmission. 19 · Device according to claim 18, characterized in that the transmitter (8) and the receiver (7) use auxiliary frequencies are controlled by the timing of the information system are won. 20. Device according to one of claims 18 or 19 »characterized in that the -other transmitter (8) and the Receiver (7) work with amplitude or frequency modulation. 21. Device arranged in a vehicle for route guidance for systems according to one of claims 1 to 17 » with a microcomputer to control the functional processes and with a transmitting and receiving device for Exchange of data with a road device, characterized in that analog-to-digital converters (U9) and Digital-to-analog converters (50) are provided for converting speech into digital signals and vice versa, and that these digital values are fed to the transceiver (U7) or are removed. 22. The device according to claim 21, characterized in that the analog-to-digital converter (1 + 8) or the digital-to-analog converter (50) registers (51> 52) are connected downstream. 23. Device according to one of claims 18 to 22, characterized characterized in that a motion sensor (6) is mounted in the vehicle and can only operate on the phone can be switched when the motion sensor (6) reports the standstill of the vehicle. 2k. Device according to one of Claims 18 to 23, characterized in that the microcomputer (1, Uo) serves as a telephone number memory and repeater. BATH ORIGINAL 25. Device according to one of claims 18 to 2k, characterized in that the device contains a card or a memory element on which charge information is contained which can be erased by pulses from the road device. 26. Device according to one of claims 18 to 25 » characterized in that a euro signal receiver is provided in addition to the vehicle device.